1. Civil Air Patrol – California Wing High Altitude and Terrain Considerations Mission Scanner Course
Chapter 7
Version 1.3 (22 February 2014)

2. Aircrew Task P-2024 Discuss Strategies to Combat High Altitude Effects

3. Objectives
Discuss the symptoms and dangers of dehydration and strategies used to combat its effects
Discuss the symptoms and dangers of ear block, sinus block and hypoxia, and strategies used to combat their effects

4. Human Performance: Dehydration
The loss of water through the skin, lungs and kidneys never ceases
Loss increases as the humidity drops with increasing altitude
Symptoms are dryness of the tissues and resulting irritation of the eyes, nose and throat
Minimize intake of coffee, tea, cola or cocoa since they contain caffeine and other chemicals
Strategies
Drink plenty of fluids; experts recommend drinking ounces of WATER (3-5 mouthfuls) thirty minutes before leaving and 4-6 ounces (a couple of mouthfuls) every fifteen minutes thereafter
Increase air flow (vents and windows)
If the search objective allows, reduce temperature by climbing to higher altitude
Objective 7.4 – Discuss the symptoms and dangers of dehydration, and strategies used to combat its effects.
Hypoxia can be insidious. It can affect you without your being aware.
The percentage of oxygen in the atmosphere is constant at about 21%, regardless of altitude. Low atmospheric pressure at altitude prevents oxygen from being absorbed into the red blood cells at high altitude
FAR’s require the pilot to breathe supplemental oxygen above 14,000.
Flight at 12,500 is limited to 30 minutes.
Ear block usually occurs during descent.
Tell the pilot as soon as an ear or sinus block occurs. It can be very painful and can cause permanent damage.
Can’t scan well while you are in pain.
Medications can affect your performance.

5. Other Effects of Altitude
Ear Block
Congestion around the Eustachian tube makes pressure equalization difficult
Can produce severe pain and a loss of hearing that can last from several hours to several days (can rupture eardrum)
Sinus Block
Sinus congestion makes pressure equalization difficult, particularly during descent
Can produce severe pain
Hypoxia
Normally not a concern for non-mountainous CAP operations (usually below 12,000 MSL)
Can have loss of night vision as low as 5,000 feet
Body has no built-in warning system against hypoxia
Everyone ’s symptoms are different
Onset altitude will vary depending upon individual
7.3.1 – 7.3.3
Objective 7.5 – Discuss the symptoms and dangers of ear block, sinus block and hypoxia, and strategies used to combat their effects.
Low atmospheric pressure at altitude prevents oxygen from being absorbed into the red blood cells at high altitude.
FARs require the pilot to breathe supplemental oxygen above 14,000; flight at 12,500 is limited to 30 minutes without supplemental oxygen.
Ear block usually occurs during descent.
Tell the pilot as soon as an ear or sinus block occurs. It can be very painful and can cause permanent damage, and you can’t scan well while you are in pain.
Medications may affect your performance.

6. Prevention Strategies
Ear Block
Yawn, swallow, tense muscles in throat
Valsalva maneuver
Sinus Block
Don’t fly if you’re not well - You will put everyone at risk. Be a professional - please speak up.
Medication usually not effective and has side effects
Hypoxia
Avoid smoking, alcohol and depressants
Supplemental oxygen

7. QUESTIONS?